monsoon illnesses affecting lungs (part 1 of 2)

Monsoon Illnesses affecting Lungs (Part 2 of 2)Dr. Manjit S. Tendolkar

Department of Chest Medicine,

Seth G. S. Medical College & K. E. M. Hospital.

LeptospirosisManagement

Introduction

Leptospirosis is a treatable disease, and hence

early diagnosis and prompt treatment are

important for the improvement of prognosis

Although, efforts to reach a definitive diagnosis

should always be undertaken, prompt institution

of pertinent therapy should take precedence, as

patients with leptospirosis are known to

demonstrate a rapid deterioration in their clinical

course

Suspecting Leptospirosis

The most characteristic clinical signs for early diagnosis are acute febrile illness of sudden onset, severe general malaise, lumbago, muscular pains and conjunctival suffusion

Proteinuria, raised erythrocyte sedimentation rate, and leucocytosis with neutrophilia are the most indicative clinical laboratory findings for early diagnosis

Serum aspartate aminotransferase (AST/SGOT), alanine aminotransferase (ALT/SGPT) and lactic dehydrogenase (LDH) levels are slightly elevated even in severe patients with jaundice. These findings are very important in differentiating between leptospirosis and viral hepatitis

Treating Leptospirosis

If the disease is not treated appropriately within

the first 2-3 days, it may progress in severity

In the olden days, immune horse serum or

specific immunoglobulin were used, and proved

to be effective when given early

Effective antimicrobial therapy should also be

initiated before the fifth day after the onset of

illness 1

General Management and

Supportive TherapyGeneral management of leptospirosis includes providing symptomatic and supportive therapy, as indicated by the nature and severity of the symptoms and signs. Bed rest is required for 1-2 weeks in the mild forms, and for 2-4 weeks in the severe forms. Return to work should be gradual. The progress is monitored with routine measurement of temperature, pulse rate and blood pressure, monitoring of the urinary output and fluid balance, and review of tests such as complete blood count, erythrocyte sedimentation rate, liver function tests, urinalysis, blood urea nitrogen (BUN), creatinine and electrolyte analysis

Chest radiograph, electrocardiogram,

determination of bleeding, clotting and

prothrombin time, and analysis of cerebrospinal

fluid are also important and are done to

determine the severity of illness and for detection

of complications.

Renal Involvement -- Restriction of fluid intake

and provision of a high carbohydrate, low protein

diet

Headache and muscular pains are treated with

analgesic agents, and fever is managed with

antipyretic agents

Intravenous injection of diazepam is very

effective in controlling convulsions

Role of appropriate fluid management strategy

titrated to clinical manifestations, state of illness

and presence or otherwise of renal involvement

cannot be over-emphasized. Oliguria due to

dehydration or hypotension should be corrected

and urine output maintained through fluid

supplementation and restitution of blood

pressure. After hydration and correction of blood

pressure, furosemide (with doses up to 1000

mg/day) may be used to ensure adequate

diuresis

Severe and worsening renal failure is treated

with dialysis. It is advisable to institute dialysis

early, as soon as BUN level reaches 200 mg/dl.

Peritoneal dialysis is preferred to haemodialysis,

as it is technically simpler.

Plasmapheresis with dialysis may be effective for

serious case with disturbance of consciousness

Management of bleeding and thrombocytopenia

may require packed cell transfusion, or platelet

transfusion, respectively

Some authorities believe in prudent use of

steroids in subjects with severe manifestations.

However, association of remarkable

haemorrhage, and macroscopic and histological

changes with steroid therapy in experimentally

infected guinea pigs cast doubts over its use 2

Chemotherapy

Penicillin kills leptospires in the logarithmic

growth phase, but not in the stationary phase

(also Erythromycin)

Streptomycin has been shown to kill leptospires

in both the logarithmic growth phase and the

stationary phase

High concentrations of tetracycline were

associated with a leptospirocidal effect, which

could not be attained with low concentrations of

the drug

Streptomycin was more effective than others in completely removing leptospires from all tissues

Although, penicillin, cephems, tetracyclines and macrolides were also effective in experimental leptospirosis, small numbers of leptospires sometimes remained in the liver and kidney

Truccolo et al. evaluated the susceptibility of leptospies to selected antimicrobial agents (ampicillin, doxycycline and ofloxacin) in a hamster model.[48] Their results demonstrated the ability of ampicillin at a high dose to clear leptospires from the host, except from kidneys and heart, where leptospires remained at day 6. Ofloxacin was unable to clear leptospires from blood or kidneys. With doxycycline, the clearance of leptospires occurred in 2 days in all the target organs studied, with the exception of liver, which required 3 days

Prognosis

Fatal outcome is mainly related to renal failure

although other features such as hyperkalaemia,

thrombocytopenia, cardiovascular failure with

hypotension and arrhythmia, and respiratory

failure with massive haemoptysis are known to

contribute to the mortality rate.

Most deaths occur between the 10th and 15th

days of illness, although death can occur as early

as the fifth day of illness in fulminant severe

cases

If the patient is not treated for the severe form

within 2-3 days after the onset of illness, it may

progress in severity and sometimes be fatal

Ventillatory Management of

ARDS3

Ventillatory Setup

Calculate predicted body weight (PBW)

Males = 50 + 2.3 [height (inches) - 60]

Females = 45.5 + 2.3 [height (inches) -60]

Select any ventilator mode

Set ventilator settings to achieve initial VT = 8 ml/kg PBW

Reduce VT by 1 ml/kg at intervals ≤ 2 hours until VT = 6ml/kg PBW.

Set initial rate to approximate baseline minute ventilation (not > 35 bpm).

Adjust VT and RR to achieve pH and plateau pressure goals below.

Oxygenation Goal: PaO2

55-80 mmHg or SpO2 88-

95% Use a minimum PEEP of 5 cm H2O.

Consider use of incremental FiO2/PEEP

combinations

Plateau Pressure Goal: ≤

30 cm H2O

Check Pplat (0.5 second inspiratory pause), at least q4h and after each change in PEEP or VT.

If Pplat > 30 cm H2O: decrease VT by 1ml/kg steps (minimum = 4 ml/kg).

If Pplat < 25 cm H2O and VT< 6 ml/kg, increase VTby 1 ml/kg until Pplat > 25 cm H2O or VT = 6 ml/kg.

If Pplat < 30 and breath stacking or dys-synchrony occurs: may increase VT in 1ml/kg increments to 7 or 8 ml/kg if Pplat remains < 30 cm H2O.

pH Goal: 7.30-7.45

Acidosis Management: (pH < 7.30)

If pH 7.15-7.30: Increase RR until pH > 7.30 or PaCO2 < 25 (Maximum set RR = 35).

If pH < 7.15: Increase RR to 35.

If pH remains < 7.15, VT may be increased in 1 ml/kg steps until pH > 7.15 (Pplat target of 30 may be exceeded).

May give NaHCO3

Alkalosis Management: (pH > 7.45) Decrease vent rate if possible.

I: E RATIO GOAL

Recommend that duration of inspiration be <

duration of expiration.

Weaning

Conduct a SPONTANEOUS BREATHING TRIAL daily when:

FiO2 ≤ 0.40 and PEEP ≤ 8.

PEEP and FiO2 ≤ values of previous day.

Patient has acceptable spontaneous breathing efforts. (May decrease vent rate by 50% for 5 minutes to detect effort.)

Systolic BP ≥ 90 mmHg without vasopressor support.

No neuromuscular blocking agents or blockade.

SPONTANEOUS

BREATHING TRIAL

(SBT): If all above criteria are met and subject has been in the study for at least 12 hours, initiate a trial of UPTO 120 minutes of spontaneous breathing with FiO2 < 0.5 and PEEP < 5:

• 1. Place on T-piece, trach collar, or CPAP ≤ 5 cm H2O with PS < 5

• 2. Assess for tolerance as below for up to two hours.

a. SpO2 ≥ 90% and/or PaO2 ≥ 60 mmHg

b. Spontaneous VT ≥ 4 ml/kg PBW

c. RR ≤ 35/min

d. pH ≥ 7.3

e. No respiratory distress (distress= 2 or more)

HR > 120% of baseline

Marked accessory muscle use

Abdominal paradox

Diaphoresis

Marked dyspnea

• 3. If tolerated for at least 30 minutes, consider extubation.

• 4. If not tolerated resume pre-weaning settings.

Refrences

1. Kobayashi Y. Clinical observation and treatment

of leptospirosis. J Infect Chemother 2001;7:59-

68.

2. Aso M. The effects of antihistamic drug, rutin and

cortisone on hemorrhage of leptospirosis

icterohaemorrhagica (In Japanese). Fukuoka

Med Acta 1955;46:188-201.

3. http://www.ardsnet.org/system/files/Ventilator%2

0Protocol%20Card.pdf

Thank You.