End of life in the intensive care unit: knowledge and practice of clinicians from Karachi, Pakistan

BACKGROUND

With improvements in the care of critically ill, physicians are faced with obligations to provide quality end-of-life care. Barriers to this include inadequate understanding of the dying patient and withdrawal or limitation of care. The objectives of this study were to document the comprehensions of physicians and nurses regarding the recognition and practice of end-of-life care for critically ill patients placed on life support in the intensive care unit.

METHODS

This was a cross-sectional study carried out at three hospitals in Karachi. Chi-squared analysis and one-way ANOVA were used to compare differences in response between the groups.

RESULTS

One hundred and thirty-seven physicians and critical care nurses completed the survey. 'Brain death' was defined as an 'irreversible cessation of brainstem function' by 85% respondents, with 50% relying on specialty consultation. Withdrawal of life support is practised by 83.2%; physicians are more likely (Chi square test P-value < 0.001) to withdraw mechanical ventilation, compared with nurses who would withdraw vasopressors (P-value 0.006). In a do not resuscitate patient, 72.3% use vasopressors, 83% initiate haemodialysis and 17.5% use non-invasive ventilation; 72.6% consult Hospital Ethics Committees; 16% respondents never withdraw life support; 28.3% considered it their responsibility to 'sustain life at all costs' and only 8% gave religious beliefs as a reason.

CONCLUSIONS

There are confusions in the definition of brain death, end-of-life recognition and indications and processes of withdrawal of life support. There are discrepancies between physicians' and nurses' perceptions and attitudes. Clearly, teaching programmes will need to incorporate cultural and religious differences in their ethics curricula.

The airway smooth muscle CCR3/CCL11 axis is inhibited by mast cells

BACKGROUND

Airway smooth muscle hyperplasia is a feature of asthma, and increases with disease severity. CCR3-mediated recruitment of airway smooth muscle progenitors towards the airway smooth muscle bundle has been proposed as one possible mechanism involved in airway smooth muscle hyperplasia. Mast cells are microlocalized to the airway smooth muscle bundle and whether mast cells influence CCR3-mediated migration is uncertain.

METHODS

We examined the expression of CCR3 by primary cultures of airway smooth muscle cells from asthmatics and nonasthmatics. CCR3 function was examined using intracellular calcium measurements, chemotaxis, wound healing, cell proliferation and survival assays. We investigated the recovery and function of both recombinant and airway smooth muscle-derived CCL11 (eotaxin) after co-culture with beta-tryptase and human lung mast cells.

RESULTS

Airway smooth muscle expressed CCR3. Airway smooth muscle CCR3 activation by CCL11 mediated intracellular calcium elevation, concentration-dependent migration and wound healing, but had no effect on proliferation or survival. Co-culture with beta-tryptase or mast cells degraded recombinant and airway smooth muscle-derived CCL11, and beta-tryptase inhibited CCL11-mediated airway smooth muscle migration.

CONCLUSIONS

CCL11 mediates airway smooth muscle migration. However co-culture with beta-tryptase or mast cells degraded recombinant and airway smooth muscle-derived CCL11 and inhibited CCL11-mediated airway smooth muscle migration. Therefore these findings cast doubt on the importance of the CCL11/CCR3 axis in the development of airway smooth muscle hyperplasia in asthma.

Comparison of combined urea and creatinine clearance and prediction equations as measures of residual renal function when GFR is low

BACKGROUND

UK, US and European guidelines recommend the decision to initiate dialysis should be based on a combination of measurements of kidney function, nutritional status and clinical symptoms. Such recommendations assume an accurate and reproducible measure of glomerular filtration rate (GFR).

METHODS

Prospective study of 97 patients with chronic kidney disease (CKD) and serum creatinine >200 micromol/l (2.26 mg/dl) who between them contributed 388 24 h urine collections. Our main outcome measure was the number of patients with low residual renal function identified by different tests, using widely accepted thresholds. We calculated sensitivity, specificity, positive and negative predictive values and receiver operating characteristic curves for each comparison using a combined urea and creatinine clearance of <15 ml/min to indicate the likely presence of end stage renal disease (CKD stage 5).

RESULTS

Seventy five patients had a combined urea and creatinine clearance <15 ml/min during the study. Using the highest measurement of serum creatinine for each patient, the best of the prediction equations was the 4-variable modification of diet in renal disease (MDRD) equation (area under ROC curve 0.93). This was followed by Kt/V (AUC 0.91) and Cockroft Gault with and without correction for ideal body weight (AUC 0.89). Further analyses showed that the 4-variable MDRD equation had higher NPV (64%) but lower PPV (89%) than the other tests (NPV 40-49%, PPV 92-100%), for identifying patients whose combined clearance was <15 ml/min.

CONCLUSION

The 4-variable MDRD formula is currently the best available prediction equation for GFR, but will nevertheless over estimate residual renal function when this is significantly impaired in up to 36% cases. Collection of 24 h urine samples may still have a role in the assessment of patients with stages 4 and 5 CKD.

Pulmonary eosinophilia correlates with allergen deposition to the lower respiratory tract in a mouse model of asthma

BACKGROUND

Eosinophilic infiltration into the airways is frequently associated with allergic asthma; however, the role of antigen deposition in mediating this phenomenon has not been studied in detail.

OBJECTIVE

Using a murine model of ovalbumin (OVA) allergy, we examined how differential deposition of OVA during antigen challenge affects pulmonary eosinophilia, immune response and airway hyper-reactivity (AHR).

METHODS

Differential allergen deposition to the upper respiratory tract (URT) alone or combined upper and lower respiratory tract (ULRT) was accomplished by administering OVA intranasally to either anaesthetized or unanaesthetized mice, respectively. BALB/c mice (6-7 weeks old) were sensitized with OVA-alum via the intraperitoneal route, and then challenged intranasally using OVA, with or without anaesthesia. AHR, enumeration of inflammatory cells and quantitative measurement of inflammatory cytokines and chemokines in bronchoalveolar lavage fluid (BALF), lung histopathology and immune responses were subsequently assessed.

RESULTS

In sensitized animals challenged via the ULRT route, a profound eosinophilia and goblet cell hyperplasia was observed in lung tissue. Conversely, sensitized mice receiving an identical challenge dose via the URT route alone exhibited only negligible levels of inflammation. Interestingly, AHR and OVA-specific IgG(1) and IgE systemic responses were comparable between the two groups.

CONCLUSION

This study indicates that direct exposure of allergen in the deep lung is highly correlated with airway eosinophilia and lung inflammation, but does not correlate with AHR or immune response.

Inflammatory cell microlocalisation and airway dysfunction: cause and effect?

Airway inflammation is a critical feature of the airway diseases asthma and chronic obstructive pulmonary disease (COPD). There is emerging evidence that structural cells play a key role in the development and perpetuation of the inflammatory response and are pivotal in the development of the changes in the airway structures that lead to airway remodelling. To date, little attention has been given to the localisation of inflammatory cells to airway structures or the potential interactions between these intimately located cells. However, it is likely that interactions between inflammatory and structural cells in the airway contribute enormously to the pathophysiology of asthma and COPD. Indeed, recent evidence suggests that mast cells localised to the airway smooth muscle bundle may be important in the development of airway hyperresponsiveness in asthma. In the present article, the authors aim to summarise: 1) the current understanding of which inflammatory cells locate to airway structures; 2) the proposed mechanisms that may be involved in mediating this microlocalisation; 3) the possible consequences of interactions between inflammatory and structural cells; and 4) the pressing need to investigate whether modulating these interactions is beneficial in asthma and chronic obstructive pulmonary disease.

Pre-eclampsia is associated with airway hyperresponsiveness

Several large retrospective cohort studies demonstrate that pre-eclampsia is common in asthmatics. Whether airway hyperresponsiveness (AHR), a hallmark of asthma, is associated with pre-eclampsia is unknown. We measured AHR, using a methacholine challenge, and atopy in 19 women 3-60 months postpartum following pre-eclamptic or normotensive pregnancies. The geometric mean (95% CI) concentration of methacholine required to produce a >20% fall in the forced expiratory volume in 1 second (PC20 FEV1) was 8.9 (2.2-36) mg/ml in pre-eclamptics versus 72 (32-131) mg/ml in controls (P = 0.01) and 9 (1.9-40) mg/ml in atopic pre-eclamptics without asthma versus 54 (17-174) mg/ml (P = 0.038) in matched controls. Therefore, AHR was increased in women who have had pre-eclampsia. This association and its possible mechanisms warrant further investigation.

Relation of cell viability and apoptosis with clinical remission following induction chemotherapy in ALL and AML

Evaluation of in vitro spontaneous apoptosis of acute leukemic blast cells after incubating for different time period and its correlation with clinical outcome is well documented in the literature. However, there is insufficient information available on the flowcytometric determination of cell viability immediately after separating blast cells and its correlation with the clinical response. In this study, we attempted to evaluate the relationship between viability of freshly isolated leukemic cells and the clinical response. Cell viability was evaluated in freshly isolated leukemic cells from 84 patients with acute leukemia (AL) using 7-Amino-Actinomycin D and was correlated with the clinical response following induction chemotherapy. Patients with ALL who achieved complete remission (CR) had significantly lower mean live cell (70.9%) compared to those patients who did not achieve CR (93.3%) (p=0.02). Furthermore, ALL responders had also significantly higher mean early apoptotic cell (19.4%) as compared to non responders (5%) (p=0.04). No significant difference was found in the mean live / early apoptotic cell count of responders and non responders of AML patients. The probability of obtaining CR in ALL patients was 3.7 and 2.7 times higher in those who had mean live cell count less than 70% and apoptotic cell count more than 10%, respectively. A lower cell viability and higher apoptosis in freshly isolated leukemic cells at the time of diagnosis may indicate a favorable response in patients with ALL but may not provide any sufficient information in predicting the response in AML patients to induction chemotherapy.

Reconstitution of immune responses occurs very rapidly after initiation of therapy for tuberculosis (43.54)

Introduction: Immune reconstitution syndrome is a potentially fatal sequelae of HAART therapy in 20% of patients with HIV and 3–5% with tuberculosis who begin treatment. The role of CD4+T cells in its pathogenesis is poorly understood.

Methods: This study was done under an IRB approved protocol to study MTb specific immunity. Groups based on HIV status and local or disseminated MTb were evaluated for CD4+ T cell counts, Purified Protein Derivative (PPD) induced proliferation and cytokine induction using intracellular cytokine staining for IFN γ, IL2, TNFα and CFSE dilution at predefined times before and after starting therapy.

Results: In preliminary results, the first 3 HIV negative patients with MTb exhibited striking increase in MTb specific immunity in the first week of therapy. Percentage of IFN γ producing CD4+T cells increased from 1.96 and 0.48 to 4.46 and 1.34, and of TNF α producing cells increased from 0.85 and 0.45 to 3.96 and 1.06 in 2 patients. Proliferative responses also showed marked increases. Percent dividing cells increased from 4.3, 4.4 and 16.3 at baseline to 36.9, 11.9 and 39.6 at 1 week and 54.8 and 72.3 at 4 weeks of therapy. Total number of CD4+ T cells also increased.

Conclusions: Tuberculosis like HIV causes quantitative and qualitative changes in CD4+T cells . These are rapidly reversed when therapy is begun .This data provides insight into the pathogenesis of the immune reconstitution syndrome.

Reducing ventilator-associated pneumonia rates through a staff education programme

Ventilator-associated pneumonia (VAP) is the most common nosocomial infection in patients on mechanical ventilation and results in increases in mortality, prolonged hospitalization and costs. Preventive measures for VAP are well-documented and evidence-based, yet remain poorly implemented in most intensive care units. We undertook an observational pre and post-intervention study to assess whether an educational programme focusing on preventive practices for VAP could reduce the incidence. Six hundred and seventy-seven adult patients, mechanically ventilated for >48 h were included in the study population. An evidence-based guideline for preventive practices at the bedside was developed and disseminated to the intensive care unit staff. VAP incidence rates before and after implementation of the educational programme were compared. VAP infection rates reduced by 51%, from a mean of 13.2+/-1.2 in the pre-intervention period to 6.5+/-1.5/1000 device days in the post-intervention period (mean difference 6.7; 95% CI: 2.9-10.4, P =0.02). A multidisciplinary educational programme geared towards intensive care unit staff can successfully reduce the incidence rates of VAP. Further studies will be needed to assess the impact on broader outcome measures such as costs or mortality.

A parturient with severe bullous emphysema from intravenous drug abuse

A parturient with severe talcosis-induced, bullous emphysema presented for urgent cesarean delivery. Respiratory effects of anesthesia, positioning for delivery and residual effects of postoperative analgesics all potentially affect the choice of anesthetic technique and drugs used in a patient with severe emphysema. This parturient was given epidural anesthesia for delivery and postoperative analgesia maintained with epidural infusion of bupivacaine and clonidine.

Profile of smoking amongst health staff in a primary care unit at a general hospital in Riyadh, Saudi Arabia

OBJECTIVE

Smoking is a major health problem among healthcare personnel as in other parts of the community. The objective of this study was to find out the prevalence of smoking along with influencing factors related to smoking among our staff in Alkharj Military Hospital.

METHODS

A self-administered questionnaire study. EPI-INFO statistical package was used for statistical analysis by calculating x(2) and p value < or = 0.05 as statistically significant.

RESULTS

A total of 230 completed questionnaires, 108 males and 122 females, were included with a response rate of 66%. The prevalence of smokers was (19%) ex-smokers (14%) and non-smokers (67%). Male smokers 31, (29%), x(2) =13.42, p< 0.001 were a significantly higher figure than female smokers. Smoking was significantly more among the group of employees with secondary school degrees, 6 (35.5%), p< 0.02. The majority of smokers were smoking 11-20 cigarettes per day (46.5%, x(2) = 14.80, p < 0.0001). Friends influenced, 30 (70%), p < 0.0001, smokers to start smoking, with relaxation being the most important reason 22, (51%), p< 0.001) for continuing smoking. Seventy six percent of smokers favored the establishment of a smoking cessation clinic. There was no significant difference regarding the knowledge of harmful effects of smoking among smokers, ex-smokers and non-smokers. The majority of smokers (70%) thought of stopping smoking and 58% attempted to stop smoking but most of the smokers failed due to social reasons or friends influences (44%).

CONCLUSION

Smoking prevalence is considerably high among our hospital workers. It is not only dangerous for the smokers itself but for the patients who idealize the behavior of hospital staff. Most of the smokers know that smoking is harmful to them as well as others around them but they did not succeed in quitting smoking due to various reasons. Health education combined with help from general practitioners may help to increase the quitting rate among smokers and preventing new smokers from taking up smoking.