A novel potentiometric sensor based on ZnO decorated polyaniline/coal nanocomposite for diltiazem determination

Diltiazem (DTZ) is one of the most effective medications for treating cardiovascular diseases. It has been widely used for the treatment of angina pectoris, hypertension and some types of arrhythmia. The development and application of a modified carbon paste sensor with improved detection limits for the potentiometric determination of diltiazem are the main goals of the current study. Sensitivity, long-term stability, reproducibility and improving the electrochemical performance are among the characteristics that have undergone careful examination. A modified carbon paste sensor based on β-cyclodextrin (β-CD) as ionophore, a lipophilic anionic additive (NaTPB) and a ZnO-decorated polyaniline/coal nanocomposite (ZnO@PANI/C) dissolved in dibutyl phthalate plasticizer, exhibited the best performance and Nernstian slope. The ZnO@PANI/C based sensor succeeded in lowering the detection limit to 5.0 × 10-7 through the linear range 1.0 × 10-6 to 1.0 × 10-2 mol L-1 with fast response time ≤ 10.0 s. The prepared nanomaterial was characterized using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). The surface properties of the proposed sensor were characterized by electrochemical impedance spectroscopy (EIS). The selectivity behavior of the investigated sensor was tested against a drug with similar chemical structure and biologically important blood electrolytes (Na+, K+, Mg2+, and Ca2+). The proposed analytical method was applied for DTZ analysis in pure drug, pharmaceutical products and industrial water samples with excellent recovery data.

Effect of Vitamin D supplementation in patients with liver cirrhosis having spontaneous bacterial peritonitis: a randomized controlled study

OBJECTIVE

Spontaneous Bacterial Peritonitis (SBP) is one of the most serious liver cirrhosis with ascites complications. Vitamin D (Vit D) deficiency has been associated with a high risk of infection and mortality in cirrhotic patients. Herein, the assessment of Vit D level as a prognostic marker in SBP patients and the impact of Vit D supplementation on their treatment plan was studied as well.

PATIENTS AND METHODS

Ascetic patients with SBP and Vit D deficiency were divided randomly into treatment and control groups. The control group received standard treatment without Vit D and the treatment group received standard treatment plus Vit D. Clinical monitoring of Vit D was done over 6 months.

RESULTS

At baseline, all patients in both groups revealed an elevated serum and ascetic TLC, AST, ALT, total and direct bilirubin, in addition to elevation in INR and procalcitonin (PCT) level. Univariate regression analysis confirmed that deficiency of Vit D was an independent predictor of infection and mortality (p < 0.01; Crude Hazard Ratio: 0.951). Over 6 months, the study revealed significant improvement in serum Vit D level in the treatment group (34.6 ± 9.2 and 18.3 ± 10.0 ng/mL; p < 0.001). Moreover, a statistically significant increase in survival rate (64% vs. 42%; p < 0.05) and duration (199.5 days vs. 185.5 days; p < 0.05) were recorded as well. Univariate and multivariate regression analysis confirmed that Vit D supplementation was positively correlated to survival over 6 months (p < 0.001; Adjusted Hazard Ratio: 0.895).

CONCLUSIONS

Vit D deficiency is prevalent in SBP cirrhotic patients and is used as an independent predictor of infection and death. Therefore, Vit D supplementation revealed improvement in their response to treatment.

Cutaneous anthrax in a school teacher

Cutaneous anthrax is an infection of the skin caused by Bacillus anthracis. This is a report of a case of cutaneous anthrax attending outpatients of Mymensingh Medical College Hospital in October, 2010. The infected person was a retired school teacher with a very good body build. He reported to handle cow flesh about 4-5 days ago, developed few painless papules over shin of right leg, which gradually became large bullae and blackish eschar developed over the lesion. Smears from the lesions were investigated which confirmed the causative agent B. anthracis. The patient was treated with oral Ciprofloxacin (500mg) twice daily for seven days which cured the infection as observed on his subsequent follow up visits on 7 and 14 days later. Oral Ciprofloxacin is found effective as recommended by the World Health Organization.

Assessing fluid responsiveness by stroke volume variation in mechanically ventilated patients with severe sepsis

BACKGROUND AND OBJECTIVE

Our hypothesis was that stroke volume variation during mechanical ventilation of the lungs would allow accurate prediction and monitoring of changes in cardiac index in response to fluid loading in patients with severe sepsis.

METHODS

This was a prospective clinical study in a university hospital. Ten mechanically ventilated patients with severe sepsis or septic shock were given fluid loading with 500 mL 10% hydroxyethylstarch 200/0.5 over 30 min. Before and after fluid loading pulmonary arterial occlusion pressure and central venous pressure were measured. Intrathoracic blood volume index, stroke volume variation and cardiac index were measured by the transpulmonary thermodilution technique. After verifying normal distribution of the data (skewness < 1.0) the paired t-test was used for statistical analysis.

RESULTS

After fluid loading stroke volume variation decreased significantly, whereas central venous pressure, pulmonary arterial occlusion pressure, intrathoracic blood volume index and cardiac index increased significantly. Changes of cardiac index in response to fluid loading were correlated to baseline values of stroke volume variation (r = 0.64, P = 0.02) and intrathoracic blood volume index (r = -0.73, P = 0.009). Changes in cardiac index were significantly correlated to percentage changes in stroke volume variation (r = -0.65, P < 0.001) and changes in intrathoracic blood volume index (r = 0.52, P = 0.002), whereas changes in cardiac index revealed no significant correlation to changes in central venous pressure (r = 0.28, P = 0.07) and changes in pulmonary arterial occlusion pressure (r = 0.29, P = 0.06).

CONCLUSIONS

Measuring stroke volume variation may be a useful way of guiding fluid therapy in ventilated patients with severe sepsis because it allows estimation of preload and prediction of cardiac index changes in response to fluid loading.

Constipation and its implications in the critically ill patient

BACKGROUND

Motility of the lower gut has been little studied in intensive care patients.

METHOD

We prospectively studied constipation in an intensive care unit of a university hospital, and conducted a national survey to assess the generalizability of our findings.

RESULTS

Constipation occurred in 83% of the patients. More constipated patients (42.5%) failed to wean from mechanical ventilation than non-constipated patients (0%), P<0.05. The median length of stay in intensive care and the proportion of patients who failed to feed enterally were greater in constipated than non-constipated patients (10 vs 6.5 days and 27.5 vs 12.5%, respectively (NS)). The survey found similar observations in other units. Delays in weaning from mechanical ventilation and enteral feeding were reported by 28 and 48% of the units surveyed, respectively.

CONCLUSIONS

Constipation has implications for the critically ill.

Alcohol-associated admissions to an adult intensive care unit: an audit

BACKGROUND AND OBJECTIVE

Excessive alcohol consumption is a major cause for premature death and preventable ill health in the whole population. We set out to audit admissions to the intensive care unit (ICU) of our large teaching hospital with respect to alcohol-related admissions.

METHODS

A prospective audit was conducted into alcohol-associated admissions to our university hospital adult ICU over 12 months. The following data were collected for each patient admitted: age, gender, diagnosis and amount of alcohol consumption, APACHE II score, and the probability of death.

RESULTS

Patients with definite alcohol consumption constituted 39.1% (124 patients) of all admissions (317 patients) to the ICU. In Group 1 (89 patients), the admission was directly associated with alcohol consumption, which included heavy alcohol consumption. Group 2 (35 patients) consisted of 'social drinkers'; and Group 3 was composed of patients who denied any alcohol intake. Group 1 had a high median APACHE II score of 19 (range 4-35) and a significantly higher mortality rate (41.6%) than Group 3 (18.4%, P < 0.001) or the entire sample studied (23.7%, P < 0.001). The results also demonstrated an incidence of pneumonia of 29.2% (26 patients) in alcohol-associated admissions compared with 22.8% (eight patients) in Group 2 and 21.8% (19 patients) in Group 3. Trauma admissions amounted to 11.4% of the patients studied (24/211 patients), 17 (70.8%) of whom were directly associated with alcohol and it included 11 pedestrians.

CONCLUSIONS

Alcohol may play a major role in the admission and mortality of ICU patients. Further investigations are warranted because our sample size is so small.

The Montgomery T-tube: anaesthetic problems and solutions

The Montgomery T-tube is a device used as a combined tracheal stent and an airway after laryngotracheal surgery. The device is used mostly in specialist centres for head and neck surgery, and therefore, many anaesthetists may be unfamiliar with its use. The Montgomery T-tube presents the anaesthetist with challenges both during its surgical insertion when acute loss of the airway might occur and also during induction of anaesthesia in patients who have such a tube in situ. Anaesthetists who are unfamiliar with the tube may have to resort to ingenious ways of coping with the problems of a shared airway with a T-tube, which does not have a suitable adaptor for a standard catheter mount, as well as controlling and maintaining ventilation through the device. Safe management of such patients requires careful planning. We describe the anaesthetic management of two cases to illustrate the problems associated with Montgomery tubes.

Randomized prospective double-blind placebo-controlled trial of effect of intravenous ondansetron on intraocular pressure during ophthalmic surgery

The effect of i.v. ondansetron, before induction of anaesthesia, on intraocular pressure (IOP) in patients undergoing cataract surgery was investigated. Forty patients (two groups of 20) received either ondansetron 4 mg (treatment group) or 0.9% saline (placebo group) in a double-blind controlled manner. There were no significant differences in IOP between the groups. Ondansetron had no significant effect on IOP during the study period.

Comparison of the effects of topical lignocaine spray applied before or after induction of anaesthesia on the pressor response to direct laryngoscopy and intubation

In an attempt to attenuate the cardiovascular pressor response to laryngoscopy and intubation, 30 patients presenting for routine ophthalmic surgery were studied and were randomly allocated into two groups: group A (n = 15) received direct laryngeal/tracheal lignocaine spray immediately before intubation; and group B (n = 15) received orolaryngeal lignocaine spray before the induction of anaesthesia. In both groups, general anaesthesia was induced with thiopentone 3-5 mg kg-1, followed by atracurium 0.6 mg kg-1 to facilitate tracheal intubation. Laryngoscopy and endotracheal intubation caused a significant increase in heart rate, by 28% in group A and 23% in group B (P < 0.05 in both), and in diastolic blood pressure, by 28% in group A and 24% in group B (P < 0.05 in both). In group A, the systolic blood pressure also increased significantly (by 18%) after intubation, but there was no significant change in group B. In addition, the plasma lignocaine concentrations remained well below the toxic range in both groups. It was concluded that topical lignocaine administration as an orolaryngeal spray before the induction of anaesthesia is effective in reducing but not abolishing the pressor response to laryngoscopy and endotracheal intubation.

The histopathology of the intestine in hamsters infected with Leishmania D. infantum on top of pre-existing schistosomiasis mansoni

In general, both Schistosoma mansoni and Leishmania, d. infantum affect more or less the same human organs. While the liver is the main organ affected, the intestine follows in importance. In the present study, L.d. infantum on tip of pre-existing S. mansoni in Syrian golden hamsters had delayed the appearance of both schistosomal and leishmanial granulomas in the intestine the positive control with either parasite alone. However, the leishmanial infection suppressed the schistosomal infection. Nevertheless, both types of granulomas caused shortening and broadening of the intestinal villi. The concomitant infection with leishmaniasis infantum and schistosomiasis mansoni promote the development of many pathological changes (liver, kidneys, intestine, blood picture etc.). No doubt, these changes lead to marked changes in the typical clinical picture of both parasites. Consequently, parasitological diagnosis of visceral leishmaniasis in concomitant infection is a must as in a case of VL. and HIV.

The pathology of the heart and lung in Syrian golden hamsters experimentally infected with Leishmania d. infantum on top of pre-existing Schistosoma mansoni infection

No doubt, double and triple infections are not uncommon features in some of the developing countries. In this paper, the effect of leishmanial infantum and schistosomal mansoni infection on the heart and lung of hamsters promoted many changes not seen in positive control with either parasite alone. Of these important changes, were the presence of leishmanial cardiac granulomas and earlier pulmonary granulomas in the lung were more or less the same as in positive schistosomal control. No doubt, with pulmonary schistosomiasis mansoni dangerous disease. Moreover, additional infection with pulmonary leishmaniasis increases the dramatic clinico-pathological picture.

Renal changes in golden hamsters experimentally infected with Leishmania D. infantum on top of Schistosoma mansoni infection

In Egypt, Schistosomiasis mansoni is one of the most important parasitic disease of man. Besides, in the last two decades, indigenous cases of infantile visceral leishmaniasis have been reported. These two parasites affect the kidney causing renal histopathological changes. Thus, it was aimed to study the concomitant infection of L. d. infantum on top of S. mansoni infection in Syrian golden hamsters, the model animal for both parasites. The results showed that the renal changes were more or less the same as infection with either parasite alone. Both parasites produce mesangial cell proliferation and mesangial matrix increase. Some glomeruli showed complete replacement of the capillary tuft with structureless homogenous material. In one S. mansoni positive control hamster Schistosoma eggs were seen within granulomas and atrophic glomeruli. However, the lesihmanial infection, more or less suppressed the schistosomal infection. The leishmanial infection itself became more prominent and the renal changes it caused appeared earlier and were more obvious.

The histopathological picture of the liver of hamsters experimentally infected with Leishmania D. infantum on top of Schistosoma mansoni infection

No doubt, double and triple infection in a patient is not an uncommon phenomenon in the Old World. Consequently, the histopathological picture of the liver of Syrian golden hamsters experimentally infected with Leishmania. d. infantum on top of pre-infection with S. mansoni was studied. The results showed that the liver was markedly affected by the concomitant infection than infection with either parasite alone. The superadded Leishmania infection caused the early appearance of cell necrosis and fatty changes. The schistosomal granulomas were rounded in shape and well circumscribed. However, they were smaller in size and less in number when compared with schistosomal control. Also, there was a comparative decrease in the number of their cellular constitutions but without changing in the cell types. The schistosomal granulomas were surrounded with a rim of amastigotes laden macrophages. On the other hand, the leishmanial granulomas, were irregular in shape but comparatively increased in size and in number on the behalf of the schistosomal granulomas. Their cellular constitutions comparatively increased as well. So, it is concluded that the L.d. infantum infection on the top of S. mansoni infection suppressed the schistosomal pathological picture in the liver of hamsters.

Histopathological studies of Syrian golden hamsters experimentally infected with Leishmania D. infantum

In the 1980s, infantile visceral leishmaniasis was documented in Al Agamy (Alexandria). The causative agent is Leishmania d. infantum and the insect vector is Phlebotomus langeroni. In this paper, Syrian golden hamsters were chosen as a model animal for histopathological studies of L. d. infantum. Twenty four male hamsters were experimentally infected with L.d. infantum. Every week, two hamsters were sacrificed and parts from the liver, heart, lung, spleen, small intestine and kidney were paraffin sectioned and stained with haematoxylin and eosin or with Giemsa stain. The leishmanial granuloma was the main histopathological changes and the liver was the main organ affected. Leishmanial granulomas were common in the liver, but few in lung and small intestine. The hepatic granulomas increased in surface areas and in number in the late stage of the infection (< 6 weeks). They were formed mainly of histiocytes, less lymphocytes and very few eosinophils with necrosis inside and bridging in between granulomas mainly occurred in the late stage of infection. Neither fibrosis nor peripheral delimitation was seen. Kupffer cell hyperplasia was seen throughout the experimental period (12 weeks). The spleen showed expansion of the red pulp and atrophy of the white pulp. The kidney showed mesangial cell proliferation and the mesangial matrix increased accompanied with amyloid deposition. All the tissue sections were photographed and the results were discussed.

Sevoflurane for difficult tracheal intubation

Three patients in whom difficult tracheal intubation was expected but awake fibreoptic intubation was not feasible presented for head and neck surgery. Anaesthesia was induced rapidly and smoothly by inhalation of sevoflurane followed by fibreoptic or conventional tracheal intubation.

Immunological pattern in Syrian golden hamsters experimentally infected with Schistosoma mansoni and Leishmania d. infantum

The immunoglobulins (IgG, IgM, IgE, & IgA) and the complements (C3 & C4) were studied in hamsters as result of a single infection (S. mansoni or L.d. infantum) and as concomitant infection (L.d. infantum on top of S. mansoni). The immunological pattern showed profound IgG and IgA increase in the concomitant group than either infection alone. Also, concomitant infection induced more IgE increase than either infection alone. On the other hand, C3 and C4 showed more decrease in concomitant infection. The whole results were discussed.

The effect of epidural blockade on gastric intramucosal pH in the peri-operative period

Patients undergoing major surgery are at risk of developing gut ischaemia and multiple organ failure. The gastric tonometer provides a relatively non-invasive method of assessing the adequacy of gut blood flow. Patients who develop repeated episodes of splanchnic ischaemia in the postoperative period, as evidenced by a low gastric intramucosal pH, have a higher mortality than those who do not. This randomised, controlled study was conducted to assess the effect of epidural blockade with bupivacaine on gastric intramucosal pH measurements in patients undergoing major surgery. A significantly lower proportion of patients with epidural blockade developed gastric intramucosal pH values < 7.32 postoperatively compared to controls (3/15 versus 13/16, p < 0.001). The significance of these results is discussed.

High frequency jet ventilation in the management of intra-operative tracheal injury

A patient undergoing pharyngo-oesphagectomy with gastric transposition sustained a large tracheal tear during the blind oesophageal dissection. High frequency jet ventilation was successfully employed in the acute airway management and continued postoperatively.

Reproducibility and comparison of cardiac output measurement by transthoracic bioimpedance and thermodilution methods in critically ill patients

The short-term reproducibility in cardiac output (CO) and stroke volume (SV) measurements by transthoracic electrical bioimpedance (TEB) and thermodilution (TH) and their agreement were studied in 31 consecutive patients in the Intensive Care Unit (ICU). For comparison of changes in CO and SV, six patients were studied separately. TEB data were not obtainable in four patients due to interference with impedance signals or heart rate detection. Both methods were reproducible. For TEB, the mean difference of duplicate measurements was 0.03 (SD 0.3) l/min for CO and 0.3 (SD 3.2) ml for SV. For TH, it was -0.04 (SD 0.5) l/min for CO and 0.6 (SD 6.6) ml for SV. The coefficient of reproducibility for CO was thus 0.6 l/min for TEB and 1.0 l/min for TH and that for SV was 6.4 ml for TEB and 13.2 ml for TH. There was no agreement in absolute CO or SV between the methods; TEB giving lower absolute readings. The mean difference (TH-TEB) was 1.4 (SD 1.4) l/min for CO and 14 (SD 13.4) ml for SV. There was, however, good correlation between the two methods. For CO, the regression equation was TEB=0.623+0.739 (TH); (p less than 0.0005, r=0.87). For SV, the regression equation was TEB=-0.23+0.823 (TH); (p less than 0.0005, r=0.86). When only changes were considered, the mean difference (TH-TEB) was -0.5 (SD 0.9) l/min for CO and -4 (SD 8) ml for SV. There was significant correlation in the changes detected by each method.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevention of bacterial infection and sepsis in acute severe pancreatitis

Between 1984 and 1986 six patients with acute respiratory failure (requiring ventilation for at least 3 days) complicating acute pancreatitis were managed on the intensive care unit (median ventilation period 6 days; range 3-41 days). Between 1987 and 1989 nine similar patients were managed (median ventilation period 35 days, range 4-69 days), and a regimen of enteral tobramycin, polymyxin and amphotericin to selectively decontaminate the digestive tract (SDD) was introduced. Five of six patients treated before 1987 had serious infections (three Gram-negative, one fungal), compared with only one of nine patients treated with SDD (P < 0.05). Clinical signs of sepsis were evident for 62% of the pre-SDD period, compared with 39% of the period during SDD therapy (P < 0.001). Systemic antibiotic prescribing was reduced in the SDD group; however, mortality remained unaffected with only two patients surviving pre-SDD and three during SDD treatment. SDD reduces infection rates and sepsis in patients with acute pancreatitis and may help to improve the prognosis of this life-threatening condition.

Peribulbar anaesthesia: failure to abolish the oculocardiac reflex

Peribulbar anaesthesia is a form of regional anaesthesia which has been used with increasing popularity in cataract surgery. Recently indications for its use have been extended to include surgery for vitreo-retinal disease and strabismus. This study shows that in nine of 11 patients in whom the oculocardiac reflex was stimulated by traction on an extra-ocular muscle, peribulbar anaesthesia failed to abolish the reflex. In each of these patients, the reflex manifested as a bradycardia. In one subject, the bradycardia was profound, showing no QRS complex for five seconds. We recommend that cardiac rhythm be monitored throughout procedures performed under peribulbar anaesthesia, and that a vagolytic agent be available for immediate use.

Effects of timolol ophthalmic solution on the intra-ocular pressure rise induced by suxamethonium and tracheal intubation

Thirty patients received topical application of either timolol ophthalmic solution 0.25%, or normal saline, 2 h before elective ophthalmic surgery in a double-blind study. The responses to suxamethonium and tracheal intubation were compared by measuring intra-ocular pressure before induction of anaesthesia, 1 min after administration of thiopentone 2-4 mg.kg-1, 1 min after administration of suxamethonium 1 mg.kg-1, and 1, 2.5 and 5 min after tracheal intubation. There was no significant difference between the groups.

Nitrous oxide and internal tamponade during vitrectomy

We analysed the nitrous oxide composition of the intraocular gas bubble following vitrectomy and fluid-air exchange in 12 patients. Samples were taken under standardised conditions at 20 minutes after completion of the fluid-air exchange. Analysis was conducted by a Medishield MS2 mass spectrometer. The percentage composition of nitrous oxide in the samples varied between 4 and 21% (mean 9%). This influx of nitrous oxide was associated with an increase of intraocular pressure. Pressure rises of greater than 20 mm Hg were not seen owing to venting of gas through the sclerostomies. An inverse relationship was noted between the extent of retinal detachment preoperatively and the amount of nitrous oxide entering the eye. A possible explanation for this relationship is proposed. The importance of nitrous oxide movement is stressed.

The cost of an intensive care unit: a prospective study

The cost of intensive care for patients admitted to the ICU were estimated. Patients suffering from severe combined acute respiratory and renal failure who required mechanical ventilation and renal replacement therapy (SCARRF-D) cost per day significantly more than non-renal patients (pounds 938 compared to pounds 653 per patient respectively) and their average length of stay in hospital is nearly 4 times as long (28.8 compared to 7.6 days respectively). Approximately 44% of the total cost was staff related (28% for the provision of nurses and 16% for the rest). Retrieving information related to cost was difficult, time consuming and labour intensive.

Multiple organ failure--a role for plasma exchange?

Two patients with multiple organ failure, septicaemia and a deteriorating clinical course were treated by plasma exchange in addition to standard supportive measures. Dramatic improvements were seen in cardio-respiratory (patient 1), neurological and renal parameters (patient 2) which were attributable to the exchanges. Plasma exchange might be of value as adjunctive therapy where overwhelming septicaemia occurs with multiple organ failure.

Reducing sepsis in severe combined acute renal and respiratory failure by selective decontamination of the digestive tract

Fifteen patients with severe combined acute renal and respiratory failure (SCARRF), who required mechanical ventilation and renal replacement therapy for at least 5 days, were treated with a regimen to selectively decontaminate the digestive tract (SDD). In these patients the incidence of significant infection was compared with the infection rate in 12 similar patients with SCARRF who had not received SDD, treated over the preceding 12 months. Both groups were comparable for age, study period, sepsis score, and therapeutic intervention scoring system on admission, although the Acute Physiology and Chronic Health Evaluation score was higher (p less than .05) in the SDD-treated group. Ten (83%) of 12 control patients developed definable infections compared with five (33%) of 15 in the SDD group (p less than .05). Gram-negative bacteria and fungi were responsible for 14 of the 17 infections affecting ten control patients, compared with six of the seven infections in only four SDD patients (p less than .05). The most notable site to benefit was the respiratory tract, with only one patient in the SDD group developing a pulmonary infection compared with five in the control patients (p less than .05). Urine infections may have been reduced from six (50%) of the 12 control patients to two (13%) of the 15 SDD patients, but this difference was not significant. Although survival in the control and SDD group was comparable (42% vs. 40%), mortality overall seemed related to infection. Eleven (73%) of 15 patients with definite infection died, in contrast with five (42%) of 12 who had no infections, although this was not significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of nebulized lignocaine on the intraocular pressure responses to tracheal intubation

We have examined the effect of preoperative administration of nebulized lignocaine or saline on the intraocular pressure (IOP) response to tracheal intubation in 20 adults. In the saline group, tracheal intubation was associated with a significant increase in IOP above control and preintubation values (P less than 0.01); in the lignocaine group there was no change in IOP following intubation. After intubation, IOP was significantly less in the lignocaine group than in the saline group (P less than 0.05).

The Keeler Pulsair air impulse tonometer. Comparison with the Perkins hand-held applanation tonometer for peri-operative measurement of intra-ocular pressure

The Keeler Pulsair is a noncontact tonometer which can be used by those without specialist ophthalmic training. The instrument was compared, in a series of 30 patients in whom a total of 150 readings were taken, in respect of accuracy, ease and speed of use, and acceptability to patients, with the Perkins hand-held applanation tonometer. There was good correlation between measurements obtained with the two instruments: r = 0.92, (p less than 0.001); the Pulsair was described as easy to use in 87% of subjects, and no patient found the procedure unpleasant. The median times taken for Pulsair measurements were 7 (range 4-14) seconds for a single reading in conscious patients, and 11 (range 4-29) seconds for four readings in anaesthetised patients. These times were significantly quicker than those recorded with the Perkins tonometer which were 83 (range 66-138) seconds and 20 (range 8-45) seconds respectively (p less than 0.001). We conclude that the Pulsair is suitable for use by those who are not ophthalmologists for the rapid measurement of intra-ocular pressure changes during anaesthesia.

Modification by fentanyl and alfentanil of the intraocular pressure response to suxamethonium and tracheal intubation

We have measured in a double-blind study the changes in intraocular pressure (IOP) in 40 consecutive patients (pretreated with fentanyl or alfentanil) who received suxamethonium and tracheal intubation. Although IOP increased significantly following administration of suxamethonium, mean IOP in both groups remained significantly less than control values (P less than 0.002). Tracheal intubation caused a further significant increase in IOP in the fentanyl, but not the alfentanil group. There were no significant differences in mean IOP between the fentanyl and alfentanil groups. Both opioids reduced, but did not abolish the haemodynamic responses to tracheal intubation.

An unusual cause of stridor following anaesthesia requiring tracheostomy

A 75-year-old woman underwent panendoscopy and excision of a neck "lump". After antagonism of residual neuromuscular block and extubation of the trachea, she developed recurrent upper airway obstruction and stridor, necessitating a permanent tracheostomy. The possibility of vagal nerve involvement or injury should always be considered during excision of neck lumps. Preoperative indirect, atraumatic laryngoscopy by experienced surgeons is essential, as are tracheal intubation and vigilant postoperative observation.

Hypotension and bradycardia following superior laryngeal nerve block

Severe hypotension and bradycardia occurred in two patients after superior laryngeal nerve block for awake tracheal intubation. Both patients required treatment with anticholinergic drugs and i.v. infusions and made a good recovery.

Anaesthesia and acute dermatomyositis/polymyositis

The anaesthetic management of two patients with severe muscle weakness--one suffering from acute dermatomyositis, the other from acute polymyositis--is described. Both patients presented for surgery for malignancy. Anaesthesia was induced with etomidate in one, thiopentone in the other. Alfentanil was used for analgesia and atracurium for muscle paralysis in both. Neuromuscular blockade was monitored using a peripheral nerve stimulator and no problems were experienced. Recovery of neuromuscular transmission and ventilatory function after operation were normal.

Contralateral haemothorax: a late complication of subclavian vein cannulation

Contralateral haemothorax developed as a late complication of subclavian vein cannulation following gradual erosion of the wall of the superior vena cava by the tip of the catheter. The use of a relatively rigid catheter and a left-sided approach may have contributed to this rare, but potentially fatal complication.