Treatment of lithium intoxication with continuous venovenous hemodiafiltration

Use of the anion gap and intermittent hemodialysis following continuous hemodiafiltration in extremely high dose acute-on-chronic lithium poisoning: A case report

A 35-year-old woman intentionally took 40,000 mg of lithium carbonate, and she was transferred to our hospital with nausea, vomiting, and diarrhea. She was diagnosed as having bipolar disorder 10 years ago and was receiving oral lithium therapy. Blood test results on arrival were remarkable for a negative anion gap of -2.1 and later, the serum lithium level turned out to be as high as 15.4 mEq/L. Intubation was required because of disrupted consciousness, and continuous hemodiafiltration (CHDF) was immediately started in the intensive care unit to obtain constant removal of lithium. After adding intermittent hemodialysis (IHD) twice during the daytime to accelerate the lithium clearance, CHDF became unnecessary on day 4, and she was extubated on day 6 with complete recovery of consciousness. Close monitoring of the patient data showed recovery of the decreased anion gap as indicator of the serum lithium level reduction. On day 36, she was discharged without any complication and sequela. The current case highlighted the effective use of CHDF between IHD sessions to prevent the rebound elevation of lithium and the role of the anion gap as a surrogate marker of serum lithium concentration during the treatment.

Extracorporeal Treatment for Lithium Poisoning: Systematic Review and Recommendations from the EXTRIP Workgroup

The Extracorporeal Treatments in Poisoning Workgroup was created to provide evidence-based recommendations on the use of extracorporeal treatments in poisoning. Here, the EXTRIP workgroup presents its recommendations for lithium poisoning. After a systematic literature search, clinical and toxicokinetic data were extracted and summarized following a predetermined format. The entire workgroup voted through a two-round modified Delphi method to reach a consensus on voting statements. A RAND/UCLA Appropriateness Method was used to quantify disagreement, and anonymous votes were compiled and discussed in person. A second vote was conducted to determine the final workgroup recommendations. In total, 166 articles met inclusion criteria, which were mostly case reports, yielding a very low quality of evidence for all recommendations. A total of 418 patients were reviewed, 228 of which allowed extraction of patient-level data. The workgroup concluded that lithium is dialyzable (Level of evidence=A) and made the following recommendations: Extracorporeal treatment is recommended in severe lithium poisoning (1D). Extracorporeal treatment is recommended if kidney function is impaired and the [Li(+)] is >4.0 mEq/L, or in the presence of a decreased level of consciousness, seizures, or life-threatening dysrhythmias irrespective of the [Li(+)] (1D). Extracorporeal treatment is suggested if the [Li(+)] is >5.0 mEq/L, significant confusion is present, or the expected time to reduce the [Li(+)] to <1.0 mEq/L is >36 hours (2D). Extracorporeal treatment should be continued until clinical improvement is apparent or [Li(+)] is <1.0 mEq/L (1D). Extracorporeal treatments should be continued for a minimum of 6 hours if the [Li(+)] is not readily measurable (1D). Hemodialysis is the preferred extracorporeal treatment (1D), but continuous RRT is an acceptable alternative (1D). The workgroup supported the use of extracorporeal treatment in severe lithium poisoning. Clinical decisions on when to use extracorporeal treatment should take into account the [Li(+)], kidney function, pattern of lithium toxicity, patient's clinical status, and availability of extracorporeal treatments.

Higher requirements of dialysis in severe lithium intoxication

Severe lithium poisoning is a frequent condition in the intoxicated intensive care unit population. Dialysis is the treatment of choice, but no clinical markers predicting higher requirement for dialysis have been identified to date. We analyze the characteristics of lithium overdose patients needing dialysis to improve lithium clearance, and identify the ones associated with higher dialysis requirement. This is an observational, retrospective study of 14 patients with lithium poisoning admitted from 2004 to 2009. Median age was 41.8 ± 16.1 years. Poisonings were acute in 7.1%, acute-on-chronic in 64.28%, and chronic in 28.5% of cases. Comparing clinical and biochemical data in patients requiring more than one dialysis session with those requiring only one session, the univariate analysis showed differences at admission in creatinine clearance (40.5 ± 23 vs. 73.3 ± 24.9 mL/min, P = 0.025), white blood cells (17,528 ± 3,530 vs. 11,580 ± 3360 cells/L, P = 0.007), and blood sodium concentration (134.8 ± 5.9 vs. 141.8 ± 8.4 mmol/L, P=0.035). We measured the degree of association between the number of sessions and the variables with partial correlations. High lithium levels (P = 0.006, r = 0.69), low creatinine clearance (P = 0.04, r = -0.55), and low blood sodium concentration (P = 0.024, r = -0.59) were associated with a greater number of dialysis sessions. The correlation remained significant for blood sodium concentration (P = 0.016, r = -0.67) after adjustment for creatinine clearance and initial lithium levels. Presence on admission of low creatinine clearance, low blood sodium concentration, and/or high lithium levels correlated with a higher number of dialysis sessions in severe lithium poisoning. These factors, especially low blood sodium concentration, are associated with higher dialysis requirements in severe lithium intoxication.

Haemodialysis followed by continuous veno-venous haemodiafiltration in lithium intoxication; a model and a case

For severe lithium intoxication haemodialysis is recommended to lower serum lithium levels rapidly. Frequently, serum lithium levels rebound after dialysis and repeated dialysis is needed. This is the first report of an adult patient with severe lithium intoxication who underwent haemodialysis (HD) followed by continuous veno-venous haemodiafiltration (CVVHDF). Mean lithium clearances with HD and CVVHDF were 173 and 61 ml/min, respectively. Serum lithium levels were rapidly lowered and did not rebound. Two compartment simulations illustrate that HD followed by CVVHDF is the most effective strategy for removing lithium from the intracellular compartment.

Evaluation of available treatment guidelines for the management of lithium intoxication

Intoxications with lithium carry considerable risk for long-term morbidity and even mortality. Consequently, any patient suspected of lithium intoxication requires immediate and appropriate care. The objectives of this study were to assess the completeness and the applicability of generally available treatment guidelines for the management of patients with a lithium intoxication and, hence, to provide general recommendations for improvement of existing treatment guidelines. Nineteen treatment guidelines originating from 7 different countries were gathered by searching the Internet, online databases, and textbooks and by contacting different poison information centers and university medical centers. A list of items was composed from the retrieved treatment guidelines and a further literature search. Most relevant items were present in the various guidelines. However, in some guidelines, essential information was missing or potentially hazardous information was provided. Clarity, presentation, and applicability of the guidelines, as assessed using parts of the Appraisal of Guidelines Research and Evaluation instrument, were relatively poor. Regular updates of treatment guidelines should be performed to incorporate new essential information. To improve applicability of guidelines, unambiguous key recommendations, alternative treatments, and special care requirements should be provided and authors are recommended to test treatment guidelines using a panel of less experienced caregivers in a hypothetical case scenario.

The role of continuous renal replacement therapy in the treatment of poisoning

Extracorporeal elimination of drugs and toxins is a critical component in the management of poisonings, though specific techniques and indications remain a matter of debate. Conventional hemodialysis is frequently the treatment of choice because of its widespread availability and proven effectiveness for certain drugs and toxins. With the increased availability of continuous renal replacement therapy (CRRT) modalities, there is yet another therapeutic option, but one that has yet to find a definitive role in this field. The continuous nature of these therapies is attractive for the management of acute renal failure, but the relatively slower clearance rates as compared to conventional hemodialysis is a distinct drawback in patients with acute xenobiotic-induced toxicity. There are abundant case reports as well as a few small case series in the medical literature documenting the use of CRRT, but specific techniques and the clinical outcomes vary considerably. Therefore one cannot draw definitive conclusions regarding benefit. Some patients, particularly those who are hemodynamically unstable and are not candidates for conventional hemodialysis, may warrant a trial of CRRT. However, at the present time, routine use for the treatment of poisoning is not supported. Controlled trials to better clarify its role would be beneficial, though such studies would be extremely difficult to conduct in this field. We believe that the intelligent application of extracorporeal modalities requires a thorough knowledge of drug pharmacokinetics, of the techniques utilized, and a skeptical analysis of the available literature.

Use of continuous venovenous hemodiafiltration in a case of severe phenobarbital poisoning

Conventional hemodialysis and hemoperfusion have been used for life-threatening phenobarbital poisoning. We report the successful use of continuous renal replacement therapy in a case of severe phenobarbital poisoning associated with severe coma and hypotension. Use of this modality led to clearance of phenobarbital with improvement in the clinical status of the patient.

Comparison of lithium concentrations in red blood cells and plasma in samples collected for TDM, acute toxicity, or acute-on-chronic toxicity

BACKGROUND

Lithium salts (Li+) are still one of the most appropriate treatments in manic-depressive disorders. Since Li+ has a narrow therapeutic index, plasma levels must be closely monitored to verify maintenance pharmacotherapy, to prevent side effects, to evaluate compliance and to avoid increasing rates of relapse. Although it has been reported that Li+ concentrations in red blood cells (RBC) should be a better indicator of brain levels, therapeutic drug monitoring (TDM) of Li+ is not based on its routine assessment.

OBJECTIVE

The aim of this retrospective study was to compare Li+ concentrations in RBC and plasma and the calculated ratio (LiR= RBC/plasma concentrations) in the three groups of patients.

METHODS

During the past 3 years, 309 Li+ measures were collected corresponding to 165 patients classified into three subgroups (TDM, acute or acute-on-chronic intoxication). Li+ plasma (Cplasma) and RBC (CRBC) concentrations were determined by atomic absorption spectrophotometry.

RESULTS

Results showed that Li+ concentrations in plasma are significantly correlated to Li+ concentration in RBC (r=0.81, P<0.0001). Although a wide inter- and intra-variability was found, Cplasma, CRBC and LiR were statistically different in the three groups. Compared with TDM, Cplasma was more elevated in cases of acute intoxication whereas Li+ accumulated preferentially in RBC in cases of acute-on-chronic intoxication.

CONCLUSION

This study shows the interest of determining Li+ in RBC and plasma for TDM, and that LiR could be a sensitive marker of intoxication and of Li+ impregnation.

Extracorporeal therapies for acute intoxications

Intoxications frequently perturb acid-base and electrolyte status, intravascular volume, and renal function. In selected cases, extracorporeal techniques effectively restore homeostasis and augment intoxicant removal. The use of 4-methylpyrazole, an inhibitor of alcohol dehydrogenase, is a new and effective treatment for patients exposed to toxic alcohols. In this section, practical approaches to commonly encountered intoxicants and the use of extracorporeal techniques are critically reviewed.